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Keyword: astronomy

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  • Astronomy Picture of the Day -- The Creature from the Red Lagoon

    11/25/2014 8:55:15 AM PST · by SunkenCiv · 4 replies
    NASA ^ | November 25, 2014 | (see photo credit)
    Explanation: What creature lurks near the red Lagoon nebula? Mars. This gorgeous color deep-sky photograph has captured the red planet passing below two notable nebulae -- cataloged by the 18th century cosmic registrar Charles Messier as M8 and M20. M20 (upper right of center), the Trifid Nebula, presents a striking contrast in red/blue colors and dark dust lanes. Just below and to the left is the expansive, alluring red glow of M8, the Lagoon Nebula. Both nebulae are a few thousand light-years distant. By comparison, temporarily situated below them both, is the dominant "local" celestial beacon Mars. Taken late last...
  • Astronomy Picture of the Day -- Soaring over Titan

    11/24/2014 12:45:57 PM PST · by SunkenCiv · 8 replies
    NASA ^ | November 24, 2014 | (see photo credit)
    Explanation: What would it look like to fly over Titan? Radar images from NASA's robotic Cassini satellite in orbit around Saturn have been digitally compiled to simulate such a flight. Cassini has swooped past Saturn's cloudiest moon several times since it arrived at the ringed planet in 2004. The virtual flight featured here shows numerous lakes colored black and mountainous terrain colored tan. Surface regions without detailed vertical information appear more flat, while sufficiently mapped regions have their heights digitally stretched. Among the basins visualized is Kraken Mare, Titan's largest lake which spans over 1,000 kilometers long. Titan's lakes are...
  • Astronomy Picture of the Day -- Tornado and Rainbow Over Kansas

    11/23/2014 11:41:49 AM PST · by SunkenCiv · 10 replies
    NASA ^ | November 23, 2014 | (see photo credit)
    Explanation: The scene might have been considered serene if it weren't for the tornado. During 2004 in Kansas, storm chaser Eric Nguyen photographed this budding twister in a different light -- the light of a rainbow. Featured here, a white tornado cloud descends from a dark storm cloud. The Sun, peeking through a clear patch of sky to the left, illuminates some buildings in the foreground. Sunlight reflects off raindrops to form a rainbow. By coincidence, the tornado appears to end right over the rainbow. Streaks in the image are hail being swept about by the high swirling winds. Over...
  • Astronomy Picture of the Day -- Solar Flare from a Sharper Sun

    11/23/2014 11:38:14 AM PST · by SunkenCiv · 6 replies
    NASA ^ | November 22, 2014 | (see photo credit)
    Explanation: Solar active region AR2192 was the largest recorded sunspot group of the last 24 years. Before rotating off the Earth-facing side of the Sun at the end of October, it produced a whopping six energetic X-class flares. Its most intense flare was captured on October 24 in this stunning view from the orbiting Solar Dynamics Observatory. The scene is a color combination of images made at three different wavelengths of extreme ultraviolet light; 193 angstroms shown in blue, 171 angstroms in white, and 304 angstroms in red. The emission, from highly ionized Iron and Helium atoms, traces magnetic field...
  • Astronomy Picture of the Day -- M1: The Crab Nebula

    11/23/2014 11:14:59 AM PST · by SunkenCiv · 15 replies
    NASA ^ | November 21, 2014 | (see photo credit)
    Explanation: The Crab Nebula is cataloged as M1, the first object on Charles Messier's famous 18th century list of things which are not comets. In fact, the Crab is now known to be a supernova remnant, debris from the death explosion of a massive star, witnessed by astronomers in the year 1054. This sharp, ground-based telescopic view uses narrowband data to track emission from ionized oxygen and hydrogen atoms (in blue and red) and explore the tangled filaments within the still expanding cloud. One of the most exotic objects known to modern astronomers, the Crab Pulsar, a neutron star spinning...
  • Astronomy Picture of the Day -- LDN 988: Dark Nebula in Cygnus

    11/23/2014 11:11:15 AM PST · by SunkenCiv · 2 replies
    NASA ^ | November 20, 2014 | (see photo credit)
    Explanation: Obscuring the rich starfields of northern Cygnus, dark nebula LDN 988 lies near the center of this cosmic skyscape. Composed with telescope and camera, the scene is some 2 degrees across. That corresponds to 70 light-years at the estimated 2,000 light-year distance of LDN 988. Stars are forming within LDN 988, part of a larger complex of dusty molecular clouds along the plane of our Milky Way galaxy sometimes called the Northern Coalsack. In fact, nebulosities associated with young stars abound in the region, including variable star V1331 Cygni shown in the inset. At the tip of a long...
  • Astronomy Picture of the Day -- Bright Spiral Galaxy M81

    11/23/2014 11:07:51 AM PST · by SunkenCiv · 3 replies
    NASA ^ | November 19, 2014 | (see photo credit)
    Explanation: One of the brightest galaxies in planet Earth's sky is similar in size to our Milky Way Galaxy: big, beautiful M81. This grand spiral galaxy can be found toward the northern constellation of the Great Bear (Ursa Major). This superbly detailed view reveals M81's bright yellow nucleus, blue spiral arms, and sweeping cosmic dust lanes with a scale comparable to the Milky Way. Hinting at a disorderly past, a remarkable dust lane actually runs straight through the disk, to the left of the galactic center, contrary to M81's other prominent spiral features. The errant dust lane may be the...
  • Astronomy Picture of the Day -- Star Formation in the Tadpole Nebula

    11/23/2014 10:51:40 AM PST · by SunkenCiv · 12 replies
    NASA ^ | November 18, 2014 | (see photo credit)
    Explanation: Dusty emission in the Tadpole nebula, IC 410, lies about 12,000 light-years away in the northern constellation Auriga. The cloud of glowing gas is over 100 light-years across, sculpted by stellar winds and radiation from embedded open star cluster NGC 1893. Formed in the interstellar cloud a mere 4 million years ago, bright cluster stars are seen all around the star-forming nebula. Notable near the image center are two relatively dense streamers of material trailing away from the nebula's central regions. Potentially sites of ongoing star formation in IC 410, these cosmic tadpole shapes are about 10 light-years long....
  • Astronomy Picture of the Day -- The Double Dust Disks of HD 95086

    11/22/2014 11:08:37 AM PST · by SunkenCiv · 6 replies
    NASA ^ | November 17, 2014 | (see photo credit)
    Explanation: What do other star systems look like? To help find out, astronomers are carrying out detailed observations of nearby stars in infrared light to see which have dust disks that might be forming planets. Observations by NASA's Spitzer Space Telescope and ESA's Herschel Space Observatory have found that planetary system HD 95086 has two dust disks: a hot one near the parent star and a cooler one farther out. An artist's illustration of how the system might appear is featured here, including hypothetical planets with large rings that orbit between the disks. The planets may have created the large...
  • Throwback Thursday: Seeing through our galaxy

    11/21/2014 10:58:31 PM PST · by LibWhacker · 7 replies
    Medium ^ | 11/20/14 | Ethan Siegel
    When we look out at the Universe, our view is pretty consistently dominated by the stars within our own galaxy. Although we know that many interesting things lie beyond — globular clusters, individual galaxies, and rich clusters and superclusters of galaxies — being in the Milky Way makes it very hard to see a great many of them. This is because our own galaxy, from our vantage point within it, dominates a huge fraction of the sky overhead. Image credit: Richard Payne, of Arizona Astrophotography.The plane of the Milky Way itself obscures about a total of 20% of our night sky. What appears...
  • NASA Builds A Time-Machine Telescope 100 Times As Powerful As The Hubble

    11/18/2014 2:32:23 PM PST · by zeestephen · 67 replies
    MSN.com ^ | 18 November 2014 | Eric Niler
    Inside a very big and very clean room at NASAs Goddard Space Flight Center in Greenbelt, Md., nearly 30 workers dressed in white protective suits, goggles and blue booties cluster around the parts of a time machine. These parts gold-covered mirrors, tennis-court-size sun shields, delicate infrared cameras are slowly being put together to become the James Webb Space Telescope.
  • Astronomy Picture of the Day -- Leonids Above Torre de la Guaita [1999]

    11/16/2014 3:33:42 AM PST · by SunkenCiv · 4 replies
    NASA ^ | November 16, 2014 | (see photo credit)
    Explanation: Leonids Meteor Shower came to an impressive crescendo in 1999. Observers in Europe saw a sharp peak in the number of meteors visible around 0210 UTC during the early morning hours of November 18. Meteor counts then exceeded 1000 per hour - the minimum needed to define a true meteor storm. At other times and from other locations around the world, observers typically reported respectable rates of between 30 and 100 meteors per hour. This photograph is a 20-minute exposure ending just before the main Leonids peak began. Visible are at least five Leonid meteors streaking high above the...
  • Astronomy Picture of the Day -- The Tulip Nebula

    11/15/2014 3:06:21 PM PST · by SunkenCiv · 2 replies
    NASA ^ | November 15, 2014 | (see photo credit)
    Explanation: Framing a bright emission region this telescopic view looks out along the plane of our Milky Way Galaxy toward the nebula rich constellation Cygnus the Swan. Popularly called the Tulip Nebula the glowing cloud of interstellar gas and dust is also found in the 1959 catalog by astronomer Stewart Sharpless as Sh2-101. About 8,000 light-years distant and 70 light-years across the complex and beautiful nebula blossoms at the center of this composite image. Red, green, and blue hues map emission from ionized sulfur, hydrogen, and oxygen atoms. Ultraviolet radiation from young, energetic stars at the edge of the Cygnus...
  • Astronomy Picture of the Day -- Welcome to a Comet

    11/15/2014 3:06:17 PM PST · by SunkenCiv · 16 replies
    NASA ^ | November 14, 2014 | (see photo credit)
    Explanation: The Rosetta Mission lander is safely on a comet. One of Philae's feet appears at the bottom left of this spectacular image of the surface of C67/P Churyumov-Gerasimenko. Still a happy lander, Philae bounced twice before settling and returning images from the surface, traveling a kilometer or so after initially touching at the targeted site Agilkia. A surface panorama suggests that the lander has come to rest tilted and near a shadowing wall, with its solar panels getting less illumination that hoped. Philae's science instruments are working as planned and data is being relayed during communications windows, when the...
  • Astronomy Picture of the Day -- Descent to a Comet

    11/13/2014 2:43:12 PM PST · by SunkenCiv · 24 replies
    NASA ^ | November 13, 2014 | (see photo credit)
    Explanation: Yesterday, the first soft landing on a comet took place some 500 million kilometers from planet Earth as the Rosetta mission lander Philae settled on the nucleus of C67/P Churyumov-Gerasimenko. The landing site, dubbed Agilkia, is located near the center of this remarkable image snapped by Philae's ROLIS (ROsetta Lander Imaging System) camera. Taken from a distance of about 3 kilometers the image has a resolution of about 3 meters per pixel at the surface. After Philae's release from the orbiter, its seven-hour long descent was made without propulsion or guidance. Following its descent the lander is in place,...
  • Astronomy Picture of the Day -- Philae Attempts Comet Nucleus Landing

    11/13/2014 2:40:03 PM PST · by SunkenCiv · 11 replies
    NASA ^ | November 12, 2014 | (see photo credit)
    Explanation: Today humanity will make its first attempt to land a probe on the nucleus of a comet. As the day progresses, the Philae (fee-LAY) lander will separate from the Rosetta spacecraft and head down to the surface of Comet 67P/ChuryumovGerasimenko. Since the texture of the comet's surface is unknown and its surface gravity is surely low, Philae will then attempt to harpoon itself down, something that has never been done before. Featured here is an artist's illustration of dishwasher-sized Philae as it might look on Comet ChuryumovGerasimenko's surface, along with explanation balloons detailing onboard scientific instruments. Many people on...
  • Astronomy Picture of the Day -- Orion in Gas, Dust, and Stars

    11/13/2014 2:37:10 PM PST · by SunkenCiv · 3 replies
    NASA ^ | November 11, 2014 | (see photo credit)
    Explanation: The constellation of Orion holds much more than three stars in a row. A deep exposure shows everything from dark nebula to star clusters, all embedded in an extended patch of gaseous wisps in the greater Orion Molecular Cloud Complex. The brightest three stars on the far left are indeed the famous three stars that make up the belt of Orion. Just below Alnitak, the lowest of the three belt stars, is the Flame Nebula, glowing with excited hydrogen gas and immersed in filaments of dark brown dust. Below and left of the frame center and just to the...
  • Astronomy Picture of the Day -- The Protoplanetary Disk of HL Tauri from ALMA

    11/13/2014 2:34:43 PM PST · by SunkenCiv · 7 replies
    NASA ^ | November 10, 2014 | (see photo credit)
    Explanation: Why does this giant disk have gaps? The exciting and probable answer is: planets. A mystery is how planets massive enough to create these gaps formed so quickly, since the HL Tauri star system is only about one million years old. The picture on which the gaps were discovered was taken with the new Atacama Large Millimeter Array (ALMA) of telescopes in Chile. ALMA imaged the protoplanetary disk, which spans about 1,500 light-minutes across, in unprecedented detail, resolving features as small as 40 light minutes. The low energy light used by ALMA was also able to peer through an...
  • Astronomy Picture of the Day -- The Cat's Eye Nebula from Hubble

    11/08/2014 9:29:02 PM PST · by SunkenCiv · 11 replies
    NASA ^ | November 09, 2014 | (see photo credit)
    Explanation: To some, it may look like a cat's eye. The alluring Cat's Eye nebula, however, lies three thousand light-years from Earth across interstellar space. A classic planetary nebula, the Cat's Eye (NGC 6543) represents a final, brief yet glorious phase in the life of a sun-like star. This nebula's dying central star may have produced the simple, outer pattern of dusty concentric shells by shrugging off outer layers in a series of regular convulsions. But the formation of the beautiful, more complex inner structures is not well understood. Seen so clearly in this digitally sharpened Hubble Space Telescope image,...
  • Astronomy Picture of the Day -- Polar Ring Galaxy NGC 660

    11/08/2014 9:27:41 AM PST · by SunkenCiv · 3 replies
    NASA ^ | November 08, 2014 | (see photo credit)
    Explanation: NGC 660 is featured in this cosmic snapshot, a sharp composite of broad and narrow band filter image data from the Gemini North telescope on Mauna Kea. Over 20 million light-years away and swimming within the boundaries of the constellation Pisces, NGC 660's peculiar appearance marks it as a polar ring galaxy. A rare galaxy type, polar ring galaxies have a substantial population of stars, gas, and dust orbiting in rings nearly perpendicular to the plane of the galactic disk. The bizarre-looking configuration could have been caused by the chance capture of material from a passing galaxy by a...
  • Astronomy Picture of the Day -- The Map of Dione

    11/06/2014 11:10:20 PM PST · by SunkenCiv · 4 replies
    NASA ^ | November 07, 2014 | (see photo credit)
    Explanation: This cylindrical projection global map is one of six new color maps of Saturn's midsized icy moons, constructed using 10 years of image data from the Cassini spacecraft. Discovered by Cassini (the astronomer) in 1684, Dione is about 1,120 kilometers across. Based on data extending from infrared to ultraviolet, the full resolution of this latest space-age map is 250 meters per pixel. The remarkable brightness difference between the tidally locked moon's lighter leading hemisphere (right) and darker trailing hemisphere clearly stands out. Like other Saturn moons orbiting within the broad E-ring, Dione's leading hemisphere is kept shiny as it...
  • Astronomy Picture of the Day -- Sh2-155: The Cave Nebula

    11/06/2014 11:07:45 PM PST · by SunkenCiv · 6 replies
    NASA ^ | November 06, 2014 | (see photo credit)
    Explanation: This colorful skyscape features the dusty Sharpless catalog emission region Sh2-155, the Cave Nebula. In the composite image, data taken through narrowband filters tracks the glow of ionized sulfur, hydrogen, and oxygen atoms in red, green, and blue hues. About 2,400 light-years away, the scene lies along the plane of our Milky Way Galaxy toward the royal northern constellation of Cepheus. Astronomical explorations of the region reveal that it has formed at the boundary of the massive Cepheus B molecular cloud and the hot, young stars of the Cepheus OB 3 association. The bright rim of ionized interstellar gas...
  • Astronomy Picture of the Day -- NGC 4762: A Galaxy on the Edge

    11/06/2014 11:04:43 PM PST · by SunkenCiv · 2 replies
    NASA ^ | November 05, 2014 | (see photo credit)
    Explanation: Why is there a bright line on the sky? What is pictured above is actually a disk galaxy being seen almost perfectly edge on. The image from the Hubble Space Telescope is a spectacular visual reminder of just how thin disk galaxies can be. NGC 4762, a galaxy in the nearby Virgo Cluster of Galaxies, is so thin that it is actually difficult to determine what type of disk galaxy it is. Its lack of a visible dust lane indicates that it is a low-dust lenticular galaxy, although it is still possible that a view from on top would...
  • Titanic Liquid: Blinding Sunglint Shines On Saturns Swampy Moon

    11/03/2014 5:34:44 PM PST · by BenLurkin · 11 replies
    universetoday.com ^ | November 3, 2014 | Elizabeth Howell
    Thats what the Sun looks like reflecting off the seas of Titan, that moon of Saturn that excites astrobiologists because its chemistry resembles what early Earth could have looked like. This image represents the first time this sunglint and Titans northern polar seas have been captured in one mosaic, NASA said. Whats more, if you look closely at the sea surrounding the sunlight, you can see what scientists dub a bathtub ring. Besides looking pretty, this image from the Cassini spacecraft shows the huge sea (called Kraken Mare) was actually larger at some point in Titans past. The southern portion...
  • Astronomy Picture of the Day -- Moon and Earth from Chang'e 5-T1

    11/03/2014 9:12:47 PM PST · by SunkenCiv · 4 replies
    NASA ^ | November 04, 2014 | (see photo credit)
    Explanation: Described at times as a big blue marble, from some vantage points Earth looks more like a small blue marble. Such was the case in this iconic image of the Earth and Moon system taken by the Chang'e 5-T1 mission last week. The Moon appears larger than the Earth because it was much closer to the spacecraft's camera. Displaying much of a surface usually hidden from Earth, the Moon appears dark and gray when compared to the more reflective and colorful planet that it orbits. The robotic Chang'e 5-T1 spacecraft, predominantly on an engineering test mission, rounded the Moon...
  • Astronomy Picture of the Day -- In Green Company: Aurora over Norway

    11/03/2014 4:17:15 AM PST · by SunkenCiv · 4 replies
    NASA ^ | November 03, 2014 | (see photo credit)
    Explanation: Raise your arms if you see an aurora. With those instructions, two nights went by with, well, clouds -- mostly. On the third night of returning to same peaks, though, the sky not only cleared up but lit up with a spectacular auroral display. Arms went high in the air, patience and experience paid off, and the amazing featured image was captured. The setting is a summit of the Austnesfjorden fjord close to the town of Svolvear on the Lofoten islands in northern Norway. The time was early March. Our Sun has been producing an abundance of picturesque aurora...
  • Astronomy Picture of the Day -- Titan Beyond the Rings

    11/02/2014 3:09:25 AM PST · by SunkenCiv · 11 replies
    NASA ^ | November 02, 2014 | (see photo credit)
    Explanation: When orbiting Saturn, be sure to watch for breathtaking superpositions of moons and rings. One such picturesque vista was visible recently to the robot Cassini spacecraft now orbiting Saturn. In 2006 April, Cassini captured Saturn's A and F rings stretching in front of cloud-shrouded Titan. Near the rings and appearing just above Titan was Epimetheus, a moon which orbits just outside the F ring. The dark space in the A ring is called the Encke Gap, although several thin knotted ringlets and even the small moon Pan orbit there.
  • Astronomy Picture of the Day -- The Day After Mars

    10/31/2014 9:37:30 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | November 01, 2014 | (see photo credit)
    Explanation: October 31, 1938 was the day after Martians encountered planet Earth, and everything was calm. Reports of the invasion were revealed to be part of a Halloween radio drama, the now famous broadcast based on H.G. Wells' scifi novel War of the Worlds. On Mars October 20, 2014 was calm too, the day after its close encounter with Comet Siding Spring. Not a hoax, this comet really did come within 86,700 miles or so of Mars, about 1/3 the Earth-Moon distance. Earth's spacecraft and rovers in Mars orbit and on the surface reported no ill effects though, and had...
  • Astronomy Picture of the Day -- Milky Way over Devils Tower

    10/31/2014 12:44:10 PM PDT · by SunkenCiv · 15 replies
    NASA ^ | October 31, 2014 | (see photo credit)
    Explanation: A mysterious formation known as Devils Tower rises into the dark above northeastern Wyoming's prairie landscape in this 16 frame panoramic view. Seen against the night sky's thin, pale clouds and eerie green airglow, star clusters and nebulae of the Milky Way arc toward the galaxy's central realm at right. Of course the scene contains the Milky Way's own haunting and grisly visages of halloween, including ghosts, a flaming skull, a glowing eye and a witch's broom. To find them, slide your cursor over the picture or just follow this link, if you dare. And have a safe and...
  • Astronomy Picture of the Day -- A Spectre in the Eastern Veil

    10/31/2014 12:40:02 PM PDT · by SunkenCiv · 17 replies
    NASA ^ | October 30, 2014 | (see photo credit)
    Explanation: Frightening forms and scary faces are a mark of the Halloween season. They also haunt this cosmic close-up of the eastern Veil Nebula. The Veil Nebula itself is a large supernova remnant, the expanding debris cloud from the death explosion of a massive star. While the Veil is roughly circular in shape and covers nearly 3 degrees on the sky in the constellation Cygnus, this portion of the eastern Veil spans only 1/2 degree, about the apparent size of the Moon. That translates to 12 light-years at the Veil's estimated distance, a reassuring 1,400 light-years from planet Earth. In...
  • Astronomy Picture of the Day -- Iridescent Cloud Edge Over Colorado

    10/31/2014 12:38:22 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | October 29, 2014 | (see photo credit)
    Explanation: Sometimes your eclipse viewing goes bad in an interesting way. While watching and photographing last Thursday's partial solar eclipse, a popular astronomy blogger suffered through long periods of clouds blocking the Sun. Unexpectedly, however, a nearby cloud began to show a rare effect: iridescence. Frequently part of a more familiar solar corona effect, iridescence is the diffraction of sunlight around a thin screen of nearly uniformly-sized water droplets. Different colors of the sunlight become deflected by slightly different angles and so come to the observer from slightly different directions. This display, featured here, was quite bright and exhibited an...
  • Astronomy Picture of the Day -- Retrograde Mars

    10/31/2014 12:35:52 PM PDT · by SunkenCiv · 2 replies
    NASA ^ | October 28, 2014 | (see photo credit)
    Explanation: Why would Mars appear to move backwards? Most of the time, the apparent motion of Mars in Earth's sky is in one direction, slow but steady in front of the far distant stars. About every two years, however, the Earth passes Mars as they orbit around the Sun. During the most recent such pass starting late last year, Mars as usual, loomed large and bright. Also during this time, Mars appeared to move backwards in the sky, a phenomenon called retrograde motion. Featured here is a series of images digitally stacked so that all of the stars coincide. Here,...
  • Astronomy Picture of the Day -- Plane, Clouds, Moon, Spots, Sun

    10/31/2014 12:31:55 PM PDT · by SunkenCiv · 4 replies
    NASA ^ | October 27, 2014 | (see photo credit)
    Explanation: What's that in front of the Sun? The closest object is an airplane, visible just below the Sun's center and caught purely by chance. Next out are numerous clouds in Earth's atmosphere, creating a series of darkened horizontal streaks. Farther out is Earth's Moon, seen as the large dark circular bite on the upper right. Just above the airplane and just below the Sun's surface are sunspots. The main sunspot group captured here, AR 2192, is one of the largest ever recorded and has been crackling and bursting with flares since it came around the edge of the Sun...
  • Astronomy Picture of the Day -- Too Close to a Black Hole

    10/26/2014 7:32:29 AM PDT · by SunkenCiv · 16 replies
    NASA ^ | October 26, 2014 | (see photo credit)
    Explanation: What would you see if you went right up to a black hole? Featured is a computer generated image highlighting how strange things would look. The black hole has such strong gravity that light is noticeably bent towards it - causing some very unusual visual distortions. Every star in the normal frame has at least two bright images - one on each side of the black hole. Near the black hole, you can see the whole sky - light from every direction is bent around and comes back to you. The original background map was taken from the 2MASS...
  • Astronomy Picture of the Day -- Sunspots and Solar Eclipse

    10/26/2014 7:25:56 AM PDT · by SunkenCiv · 1 replies
    NASA ^ | October 25, 2014 | (see photo credit)
    Explanation: A New Moon joined giant sunspot group AR 2192 to dim the bright solar disk during Thursday's much anticipated partial solar eclipse. Visible from much of North America, the Moon's broad silhouette is captured in this extreme telephoto snapshot near eclipse maximum from Santa Cruz, California. About the size of Jupiter, the remarkable AR 2192 itself darkens a noticeable fraction of the Sun, near center and below the curved lunar limb. As the sunspot group slowly rotates across the Sun and out of view in the coming days its activity is difficult to forecast. But the timing of solar...
  • Astronomy Picture of the Day -- AR 2192: Giant on the Sun

    10/26/2014 7:22:29 AM PDT · by SunkenCiv · 2 replies
    NASA ^ | October 24, 2014 | (see photo credit)
    Explanation: As you (safely!) watched the progress of yesterday's partial solar eclipse, you probably also spotted a giant sunspot group. Captured in this sharp telescopic image from October 22nd the complex AR 2192 is beautiful to see, a sprawling solar active region comparable in size to the diameter of Jupiter. Like other smaller sunspot groups, AR 2192 is now crossing the Earth-facing side of the Sun and appears dark in visible light because it is cooler than the surrounding surface. Still, the energy stored in the region's twisted magnetic fields is enormous and has already generated powerful explosions, including two...
  • Astronomy Picture of the Day -- Galaxies in Pegasus

    10/26/2014 7:19:16 AM PDT · by SunkenCiv · 2 replies
    NASA ^ | October 23, 2014 | (see photo credit)
    Explanation: This wide, sharp telescopic view reveals galaxies scattered beyond the stars and faint dust nebulae of the Milky Way at the northern boundary of the high-flying constellation Pegasus. Prominent at the upper right is NGC 7331. A mere 50 million light-years away, the large spiral is one of the brighter galaxies not included in Charles Messier's famous 18th century catalog. The disturbed looking group of galaxies at the lower left is well-known as Stephan's Quintet. About 300 million light-years distant, the quintet dramatically illustrates a multiple galaxy collision, its powerful, ongoing interactions posed for a brief cosmic snapshot. On...
  • Astronomy Picture of the Day -- Sunspot Group AR 2192 Crackles

    10/26/2014 7:15:37 AM PDT · by SunkenCiv · 2 replies
    NASA ^ | October 22, 2014 | (see photo credit)
    Explanation: One of the largest sunspot groups in recent years is now crossing the Sun. Labelled Active Region 2192, it has already thrown a powerful solar flare and has the potential to produce more. The featured video shows a time lapse sequence of the Sun in visible and ultraviolet light taken yesterday and incorporating the previous 48 hours. AR 2192, rotating in from the left, rivals Jupiter in size and is literally crackling with magnetic energy. The active Sun has caused some spectacular auroras in recent days, and energetic particles originating from AR 2192 may help continue them over the...
  • Astronomy Picture of the Day -- Mimas: Small Moon with a Big Crater

    10/26/2014 7:11:52 AM PDT · by SunkenCiv · 9 replies
    NASA ^ | October 21, 2014 | (see photo credit)
    Explanation: Whatever hit Mimas nearly destroyed it. What remains is one of the largest impact craters on one of Saturn's smallest moons. The crater, named Herschel after the 1789 discoverer of Mimas, Sir William Herschel, spans about 130 kilometers and is pictured above. Mimas' low mass produces a surface gravity just strong enough to create a spherical body but weak enough to allow such relatively large surface features. Mimas is made of mostly water ice with a smattering of rock - so it is accurately described as a big dirty snowball. The above image was taken during the 2010 February...
  • Astronomy Picture of the Day -- Comet Siding Spring Passes Mars

    10/26/2014 7:05:16 AM PDT · by SunkenCiv · 5 replies
    NASA ^ | October 20, 2014 | (see photo credit)
    Explanation: Yesterday, a comet passed very close to Mars. In fact, Comet C/2013 A1 (Siding Spring) passed closer to the red planet than any comet has ever passed to Earth in recorded history. To take advantage of this unique opportunity to study the close interaction of a comet and a planet, humanity currently has five active spacecraft orbiting Mars: NASA's MAVEN, MRO, Mars Odyssey, as well as ESA's Mars Express, and India's Mars Orbiter. Most of these spacecraft have now sent back information that they have not been damaged by small pieces of the passing comet. These spacecraft, as well...
  • Awesome Photo Shows Monster Sunspot Aiming Our Way

    10/20/2014 1:23:32 PM PDT · by BenLurkin · 34 replies
    universetoday.com ^ | October 20, 2014 | Jason Major off
    According to Spaceweather.com AR2192 has grown considerably over the past few days and has the potential to unleash M- and X-class flares in our direction now that its moving into Earth-facing position. Its currently many times larger than Earth and will likely get even bigger in fact, during this weeks partial solar eclipse AR2192 should be visible with the naked (but not unprotected!) eye for viewers across much of North America.
  • Astronomy Picture of the Day -- Comet McNaught Over New Zealand

    10/19/2014 5:20:31 PM PDT · by SunkenCiv · 4 replies
    NASA ^ | October 19, 2014 | (see photo credit)
    Explanation: Comet McNaught was perhaps the most photogenic comet of modern times -- from Earth. After making quite a show in the northern hemisphere in early January of 2007, the comet moved south and developed a long and unusual dust tail that dazzled southern hemisphere observers. In late January 2007, Comet McNaught was captured between Mount Remarkable and Cecil Peak in this spectacular image taken from Queenstown, South Island, New Zealand. The bright comet dominates the right part of the above image, while the central band of our Milky Way Galaxy dominates the left. Careful inspection of the image will...
  • Astronomy Picture of the Day -- Melotte 15 in the Heart

    10/19/2014 5:19:04 PM PDT · by SunkenCiv · 11 replies
    NASA ^ | October 18, 2014 | (see photo credit)
    Explanation: Cosmic clouds form fantastic shapes in the central regions of emission nebula IC 1805. The clouds are sculpted by stellar winds and radiation from massive hot stars in the nebula's newborn star cluster, Melotte 15. About 1.5 million years young, the cluster stars are toward the right in this colorful skyscape, along with dark dust clouds in silhouette against glowing atomic gas. A composite of narrowband and broadband telescopic images, the view spans about 30 light-years and includes emission from ionized hydrogen, sulfur, and oxygen atoms mapped to green, red, and blue hues in the popular Hubble Palette. Wider...
  • Comet Flies By Mars Today in Rare Encounter: Watch It Online

    10/19/2014 9:23:08 AM PDT · by messierhunter · 15 replies
    Space.com ^ | 10/19/14 | Miriam Kramer
    A comet from the outer reaches of the solar system is due to give Mars a close shave on Sunday (Oct. 19), and you can watch the flyby live online. While Comet Siding Spring (also called Comet C/2013 A1) isn't easy to spot from Earth, a couple different astronomy organizations will be tracking the comet as it flies 87,000 miles (139,500 kilometers) from Mars at 2:27 p.m. EDT (1827 GMT) on Sunday. The comet will fly three times closer to Mars than the moon is to Earth.
  • Astronomy Picture of the Day -- Messier 6 and Comet Siding Spring

    10/17/2014 5:07:23 AM PDT · by SunkenCiv · 7 replies
    NASA ^ | October 17, 2014 | (see photo credit)
    Explanation: This looks like a near miss but the greenish coma and tail of Comet Siding Spring (C/2013 A1) are really 2,000 light-years or so away from the stars of open cluster Messier 6. They do appear close together though, along the same line-of-sight in this gorgeous October 9th skyscape toward the constellation Scorpius. Still, on Sunday, October 19th this comet really will be involved in a near miss, passing within only 139,500 kilometers of planet Mars. That's about 10 times closer than any known comet flyby of planet Earth, and nearly one third the Earth-Moon distance. While an impact...
  • Astronomy Picture of the Day -- Rosetta's Selfie

    10/16/2014 5:33:20 PM PDT · by SunkenCiv · 14 replies
    NASA ^ | October 16, 2014 | (see photo credit)
    Explanation: This Rosetta spacecraft selfie was snapped on October 7th. At the time the spacecraft was about 472 million kilometers from planet Earth, but only 16 kilometers from the surface of comet 67P/Churyumov-Gerasimenko. Looming beyond the spacecraft near the top of the frame, dust and gas stream away from the comet's curious double-lobed nucleus and bright sunlight glints off one of Rosetta's 14 meter long solar arrays. In fact, two exposures, one short and one long, were combined to record the dramatic high contrast scene using the CIVA camera system on Rosetta's still-attached Philae lander. Its chosen primary landing site...
  • Astronomy Picture of the Day -- Mysterious Changing feature on Titan

    10/15/2014 5:50:53 PM PDT · by SunkenCiv · 12 replies
    NASA ^ | October 15, 2014 | (see photo credit)
    Explanation: What is that changing object in a cold hydrocarbon sea of Titan? Radar images from the robotic Cassini spacecraft orbiting Saturn have been recording the surface of the cloud-engulfed moon Titan for years. When imaging the flat -- and hence radar dark -- surface of the methane and ethane lake called Ligeia Mare, an object appeared in 2013 just was not there in 2007. Subsequent observations in 2014 found the object remained -- but had changed! The featured image shows how the 20-km long object has appeared and evolved. Current origin speculative explanations include bubbling foam and floating solids,...
  • Astronomy Picture of the Day -- Auroral Corona over Norway

    10/15/2014 5:48:49 PM PDT · by SunkenCiv · 10 replies
    NASA ^ | October 14, 2014 | (see photo credit)
    Explanation: Higher than the highest mountain lies the realm of the aurora. Auroras rarely reach below 60 kilometers, and can range up to 1000 kilometers. Aurora light results from energetic electrons and protons striking atoms and molecules in the Earth's atmosphere. Somewhat uncommon, an auroral corona appears as a center point for a surrounding display and may occur when an aurora develops directly overhead, or when auroral rays are pointed nearly toward the observer. This picturesque but brief green and purple aurora exhibition occurred last month high above Kvalya, Troms, Norway. The Sessyfjorden fjord runs through the foreground, while numerous...
  • Astronomy Picture of the Day -- Sprite Lightning in Slow Motion

    10/15/2014 5:47:28 PM PDT · by SunkenCiv · 9 replies
    NASA ^ | October 13, 2014 | (see photo credit)
    Explanation: What causes sprite lightning? Mysterious bursts of light in the sky that momentarily resemble gigantic jellyfish have been recorded for over 25 years, but their root cause remains unknown. Some thunderstorms have them -- most don't. Recently, however, high speed videos are better detailing how sprites actually develop. The featured video is fast enough -- at about 10,000 frames per second -- to time-resolve several sprite "bombs" dropping and developing into the multi-pronged streamers that appear on still images. Unfortunately, the visual clues provided by these videos do not fully resolve the sprite origins mystery. They do indicate to...
  • Astronomy Picture of the Day -- The Helix Nebula from Blanco and Hubble

    10/11/2014 9:28:32 PM PDT · by SunkenCiv · 10 replies
    NASA ^ | October 12, 2014 | (see photo credit)
    Explanation: How did a star create the Helix nebula? The shapes of planetary nebula like the Helix are important because they likely hold clues to how stars like the Sun end their lives. Observations by the orbiting Hubble Space Telescope and the 4-meter Blanco Telescope in Chile, however, have shown the Helix is not really a simple helix. Rather, it incorporates two nearly perpendicular disks as well as arcs, shocks, and even features not well understood. Even so, many strikingly geometric symmetries remain. How a single Sun-like star created such beautiful yet geometric complexity is a topic of research. The...